Rare earth polishing powder rich in cerium oxide has taken the place of iron oxide as a key technical material used in glass polishing process since the 1940s. Compared with the conventional polishing powder, rare earth polishing powder has advantages of high polishing speed, high degree of finish and long service life; moreover, rare earth polishing powder is capable of improving polishing quality and operation environment. For its unique chemical mechanical functional mechanism which brings a high polishing efficiency, rare earth polishing powder has become the first choice when it comes to selecting a glass polishing material and has been widely used to polish products including eyeglass, optical elements (lens, prism), the glass shell of color TV, electronic glass for panel display, silicon wafer and the glass substrate of magnetic disk.
When used as polishing abrasive particles, the usability of cerium oxide (CeO2 is related to not only its chemical composition and purity but also its crystal type, morphology, particle size distribution, particle size and other indexes, which gives rise to a higher requirement on the control over the preparation of CeO2, thus, it is especially important to develop a CeO2 abrasive material which is highly spherized in appearance and has a uniform particle size distribution and a high polishing capability. Although quite a few CeO2 preparation technologies have been reported already, the prepared CeO2 by these technologies commonly suffer disadvantages including severe particle aggregation, non-uniform particle size distribution and unstable performance which make its usability undermined.
What is most hazardous to a polishing process are superhard particles which may cause a mechanical damage, and then superhard particles will lead to the generation of scratches on a polished surface to increase the degree of imperfection and roughness on the surface of the polished workpiece; even softly aggregated particles will also influent on the quality of the surface of the polished workpiece.